| // Copyright (c) 2010 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // This provides a way to access the application's current preferences. |
| |
| #ifndef CHROME_BROWSER_PREF_SERVICE_H_ |
| #define CHROME_BROWSER_PREF_SERVICE_H_ |
| |
| #include <set> |
| |
| #include "base/file_path.h" |
| #include "base/hash_tables.h" |
| #include "base/non_thread_safe.h" |
| #include "base/observer_list.h" |
| #include "base/scoped_ptr.h" |
| #include "base/values.h" |
| #include "chrome/browser/pref_value_store.h" |
| #include "chrome/common/pref_store.h" |
| |
| class NotificationObserver; |
| class Preference; |
| class ScopedPrefUpdate; |
| |
| class PrefService : public NonThreadSafe { |
| public: |
| |
| // A helper class to store all the information associated with a preference. |
| class Preference { |
| public: |
| |
| // The type of the preference is determined by the type of |default_value|. |
| // Therefore, the type needs to be a boolean, integer, real, string, |
| // dictionary (a branch), or list. You shouldn't need to construct this on |
| // your own, use the PrefService::Register*Pref methods instead. |
| // |default_value| will be owned by the Preference object. |
| Preference(PrefValueStore* pref_value_store, |
| const wchar_t* name, |
| Value* default_value); |
| ~Preference() {} |
| |
| Value::ValueType type() const { return type_; } |
| |
| // Returns the name of the Preference (i.e., the key, e.g., |
| // browser.window_placement). |
| const std::wstring name() const { return name_; } |
| |
| // Returns the value of the Preference. If there is no user specified |
| // value, it returns the default value. |
| const Value* GetValue() const; |
| |
| // Returns true if the current value matches the default value. |
| bool IsDefaultValue() const; |
| |
| // Returns true if the Preference is managed, i.e. set by an admin policy. |
| // Since managed prefs have the highest priority, this also indicates |
| // whether the pref is actually being controlled by the policy setting. |
| bool IsManaged() const; |
| |
| // Returns true if the Preference has a value set by an extension, even if |
| // that value is being overridden by a higher-priority source. |
| bool HasExtensionSetting() const; |
| |
| // Returns true if the Preference has a user setting, even if that value is |
| // being overridden by a higher-priority source. |
| bool HasUserSetting() const; |
| |
| // Returns true if the Preference value is currently being controlled by an |
| // extension, and not by any higher-priority source. |
| bool IsExtensionControlled() const; |
| |
| // Returns true if the Preference value is currently being controlled by a |
| // user setting, and not by any higher-priority source. |
| bool IsUserControlled() const; |
| |
| private: |
| friend class PrefService; |
| |
| Value::ValueType type_; |
| std::wstring name_; |
| scoped_ptr<Value> default_value_; |
| |
| // A reference to the pref service's pref_value_store_. |
| PrefValueStore* pref_value_store_; |
| |
| DISALLOW_COPY_AND_ASSIGN(Preference); |
| }; |
| |
| // Factory method that creates a new instance of a |PrefService| with |
| // all platform-applicable PrefStores (managed, extension, user, etc.). |
| // This is the usual way to create a new PrefService. |
| static PrefService* CreatePrefService(const FilePath& pref_filename); |
| |
| // Convenience factory method for use in unit tests. Creates a new |
| // PrefService that uses a PrefValueStore with user preferences at the given |
| // |pref_filename|, and no other PrefStores (i.e., no other types of |
| // preferences). |
| static PrefService* CreateUserPrefService(const FilePath& pref_filename); |
| |
| // This constructor is primarily used by tests. The |PrefValueStore| provides |
| // preference values. |
| explicit PrefService(PrefValueStore* pref_value_store); |
| |
| ~PrefService(); |
| |
| // Reloads the data from file. This should only be called when the importer |
| // is running during first run, and the main process may not change pref |
| // values while the importer process is running. Returns true on success. |
| bool ReloadPersistentPrefs(); |
| |
| // Returns true if the preference for the given preference name is available |
| // and is managed. |
| bool IsManagedPreference(const wchar_t* pref_name) const; |
| |
| // Writes the data to disk. The return value only reflects whether |
| // serialization was successful; we don't know whether the data actually made |
| // it on disk (since it's on a different thread). This should only be used if |
| // we need to save immediately (basically, during shutdown). Otherwise, you |
| // should use ScheduleSavePersistentPrefs. |
| bool SavePersistentPrefs(); |
| |
| // Serializes the data and schedules save using ImportantFileWriter. |
| void ScheduleSavePersistentPrefs(); |
| |
| // Make the PrefService aware of a pref. |
| void RegisterBooleanPref(const wchar_t* path, |
| bool default_value); |
| void RegisterIntegerPref(const wchar_t* path, |
| int default_value); |
| void RegisterRealPref(const wchar_t* path, |
| double default_value); |
| void RegisterStringPref(const wchar_t* path, |
| const std::string& default_value); |
| void RegisterFilePathPref(const wchar_t* path, |
| const FilePath& default_value); |
| void RegisterListPref(const wchar_t* path); |
| void RegisterDictionaryPref(const wchar_t* path); |
| |
| // These varients use a default value from the locale dll instead. |
| void RegisterLocalizedBooleanPref(const wchar_t* path, |
| int locale_default_message_id); |
| void RegisterLocalizedIntegerPref(const wchar_t* path, |
| int locale_default_message_id); |
| void RegisterLocalizedRealPref(const wchar_t* path, |
| int locale_default_message_id); |
| void RegisterLocalizedStringPref(const wchar_t* path, |
| int locale_default_message_id); |
| |
| // If the path is valid and the value at the end of the path matches the type |
| // specified, it will return the specified value. Otherwise, the default |
| // value (set when the pref was registered) will be returned. |
| bool GetBoolean(const wchar_t* path) const; |
| int GetInteger(const wchar_t* path) const; |
| double GetReal(const wchar_t* path) const; |
| std::string GetString(const wchar_t* path) const; |
| FilePath GetFilePath(const wchar_t* path) const; |
| |
| // Returns the branch if it exists. If it's not a branch or the branch does |
| // not exist, returns NULL. |
| const DictionaryValue* GetDictionary(const wchar_t* path) const; |
| const ListValue* GetList(const wchar_t* path) const; |
| |
| // If the pref at the given path changes, we call the observer's Observe |
| // method with NOTIFY_PREF_CHANGED. |
| virtual void AddPrefObserver(const wchar_t* path, NotificationObserver* obs); |
| void RemovePrefObserver(const wchar_t* path, NotificationObserver* obs); |
| |
| // Removes a user pref and restores the pref to its default value. |
| void ClearPref(const wchar_t* path); |
| |
| // If the path is valid (i.e., registered), update the pref value. |
| void Set(const wchar_t* path, const Value& value); |
| void SetBoolean(const wchar_t* path, bool value); |
| void SetInteger(const wchar_t* path, int value); |
| void SetReal(const wchar_t* path, double value); |
| void SetString(const wchar_t* path, const std::string& value); |
| void SetFilePath(const wchar_t* path, const FilePath& value); |
| |
| // Int64 helper methods that actually store the given value as a string. |
| // Note that if obtaining the named value via GetDictionary or GetList, the |
| // Value type will be TYPE_STRING. |
| void SetInt64(const wchar_t* path, int64 value); |
| int64 GetInt64(const wchar_t* path) const; |
| void RegisterInt64Pref(const wchar_t* path, int64 default_value); |
| |
| // Used to set the value of dictionary or list values in the pref tree. This |
| // will create a dictionary or list if one does not exist in the pref tree. |
| // This method returns NULL only if you're requesting an unregistered pref or |
| // a non-dict/non-list pref. |
| // WARNING: Changes to the dictionary or list will not automatically notify |
| // pref observers. |
| // Use a ScopedPrefUpdate to update observers on changes. |
| DictionaryValue* GetMutableDictionary(const wchar_t* path); |
| ListValue* GetMutableList(const wchar_t* path); |
| |
| // Returns true if a value has been set for the specified path. |
| // NOTE: this is NOT the same as FindPreference. In particular |
| // FindPreference returns whether RegisterXXX has been invoked, where as |
| // this checks if a value exists for the path. |
| bool HasPrefPath(const wchar_t* path) const; |
| |
| class PreferencePathComparator { |
| public: |
| bool operator() (Preference* lhs, Preference* rhs) const { |
| return lhs->name() < rhs->name(); |
| } |
| }; |
| typedef std::set<Preference*, PreferencePathComparator> PreferenceSet; |
| const PreferenceSet& preference_set() const { return prefs_; } |
| |
| // A helper method to quickly look up a preference. Returns NULL if the |
| // preference is not registered. |
| const Preference* FindPreference(const wchar_t* pref_name) const; |
| |
| // For the given pref_name, fire any observer of the pref only if |old_value| |
| // is different from the current value. Virtual so it can be mocked for a |
| // unit test. |
| virtual void FireObserversIfChanged(const wchar_t* pref_name, |
| const Value* old_value); |
| |
| bool read_only() const { return pref_value_store_->ReadOnly(); } |
| |
| protected: |
| // This should only be accessed by subclasses for unit-testing. |
| bool PrefIsChanged(const wchar_t* path, const Value* old_value); |
| |
| private: |
| // Add a preference to the PreferenceMap. If the pref already exists, return |
| // false. This method takes ownership of |pref|. |
| void RegisterPreference(Preference* pref); |
| |
| // Returns a copy of the current pref value. The caller is responsible for |
| // deleting the returned object. |
| Value* GetPrefCopy(const wchar_t* pref_name); |
| |
| // For the given pref_name, fire any observer of the pref. |
| void FireObservers(const wchar_t* pref_name); |
| |
| // Load from disk. Returns a non-zero error code on failure. |
| PrefStore::PrefReadError LoadPersistentPrefs(); |
| |
| // Load preferences from storage, attempting to diagnose and handle errors. |
| // This should only be called from the constructor. |
| void InitFromStorage(); |
| |
| // The value of a Preference can be: |
| // managed, user defined, recommended or default. |
| // The PrefValueStore manages enforced, user defined and recommended values |
| // for Preferences. It returns the value of a Preference with the |
| // highest priority, and allows to set user defined values for preferences |
| // that are not managed. |
| scoped_ptr<PrefValueStore> pref_value_store_; |
| |
| // A set of all the registered Preference objects. |
| PreferenceSet prefs_; |
| |
| // A map from pref names to a list of observers. Observers get fired in the |
| // order they are added. |
| typedef ObserverList<NotificationObserver> NotificationObserverList; |
| typedef base::hash_map<std::wstring, NotificationObserverList*> |
| PrefObserverMap; |
| PrefObserverMap pref_observers_; |
| |
| friend class ScopedPrefUpdate; |
| friend class TestingPrefService; |
| |
| DISALLOW_COPY_AND_ASSIGN(PrefService); |
| }; |
| |
| #endif // CHROME_BROWSER_PREF_SERVICE_H_ |